In a sharply worded ruling that struck a new blow at City Hall patronage, a federal appeals court Tuesday upheld the convictions of four men for scheming to rig hiring in Mayor Richard Daley's administration -- even though prosecutors never proved they personally benefited.

Former Daley patronage chief Robert Sorich and two co-defendants were found guilty in 2006 of ensuring that jobs and promotions were reserved for members of pro-Daley political armies that helped the mayor's endorsed candidates. A fourth defendant was convicted of lying to investigators.

A three-judge panel of the 7th U.S. Circuit Court of Appeals swatted away their key contention that they could not be convicted of criminal fraud because they took no bribes or kickbacks.

"It is hard to take too seriously the contention that the defendants did not know that by creating a false hiring scheme that provided thousands of lucrative city jobs to political cronies, falsifying documents and lying repeatedly about what they were doing, they were perpetrating a fraud," Judge Ann Williams wrote for the unanimous panel.

Williams described the mayor's Office of Intergovernmental Affairs, where Sorich worked, as "the beating heart of this fraudulent scheme."

Daley read a brief statement Tuesday evening expressing sympathy for the four defendants -- three of whom come from Daley's 11th Ward power base -- but declined to answer questions from reporters.

"The court has made its decision and there is nothing I can add to this legal debate," said Daley, who has denied any knowledge of corruption.

Daley said reforms have been instituted before adding, "I also must express my concern for the individuals and their families who have been involved in this case."

After winning the convictions in the Sorich trial, prosecutors said they would continue their investigation of City Hall corruption.

But the only high-ranking Daley administration official to face charges since has been former Streets and Sanitation Commissioner Al Sanchez, accused last year of arranging jobs for members of the pro-Daley Hispanic Democratic Organization. And no charges have come yet from investigations into hiring at Cook County and in the Blagojevich administration.

"The presumption of people in politics has been that a lot of other things were waiting on this decision," said Cook County Commissioner Mike Quigley (D-Chicago). "It backed up a very important tool to ferret out corruption."

In the corridors of power at City Hall and in Chicago's wards, the decision spread quickly among a political class that had begun adjusting to life after patronage.

"It's a new day, a new age," said Ald. Brian Doherty (41st), a longtime Daley loyalist despite being the City Council's only Republican. "Things that previously might not have been ethical but were part of the landscape are no longer there."

Doherty, who helped get a city job for a man later convicted of corruption in the Hired Truck scandal, echoed many other local politicians in his belief that federal authorities have criminalized what was at worst a violation of the civil Shakman decree, which was supposed to restrict patronage.

The shift away from using patronage workers in elections began after the hiring scandal broke in 2005, when federal agents made a midnight raid of city offices. The massive pro-Daley political armies that backed his candidates in previous years did not materialize to counter challengers in last year's City Council elections.

Sorich and Patrick Slattery, former director of staff services in the Department of Streets and Sanitation, have been free pending the appeal but may have to report to prison Friday. Sorich was sentenced to 3 years and 10 months in prison and Slattery was sentenced to 2 years and 3 months in prison.

A third defendant, Sorich aide Timothy McCarthy, began serving his 18-month sentence last year. He was set to be released Wednesday from federal prison in Oxford, Wis., to serve the remaining six weeks of his sentence at a halfway house in Chicago, his attorney, Patrick Deady, said Tuesday.

The fourth defendant, John Sullivan, a former managing deputy for the city's Streets and Sanitation Department, was convicted of lying to federal agents.

At least three of the former aides plan to appeal, their attorneys said Tuesday.

A spokesman for U.S. Atty. Patrick Fitzgerald's office declined to comment. But experts said the ruling was highly important for authorities who rely heavily on the so-called honest services fraud charge in public corruption cases. In such cases, prosecutors allege that an official deprived the public of their "honest services" by making corrupt decisions based on concealed conflicts of interest.

Williams' opinion "was written in very strong terms, leaving very little in question," said Scott Mendeloff, a Chicago attorney and former federal prosecutor.